A variety of service and collaborative projects in protein identification have been or are being carried out within the Mass Spectrometry Research and Support Group with approximately 5000 samples analyzed from 33 scientists representing 21 principal investigators or core heads from 8 laboratory branches and the DNTP. One large effort is in support of the protein expression function of the Structural Biology Core Laboratory and Dr. Bob Petrovich. The Role of the MSRSG is to confirm gene expression at the protein level prior to the Structural Biology Core Laboratory handing materials over to their users. Other unpublished projects that are still ongoing include: Identification of bacterial pathogens by MALDI-MS David Kurtz Identification of binding partners of NTHL1 (Doetsch); Rubicon (Martinez); Grc3/Las1 (Stanley); TSEN (Stanley); SMCHD1 (Shaw); uncharacterized esterase (Williams); VRK1 (Negishi) Additional projects focused on the identification of proteins that interacted with RNA elements (Hall). Additional projects that have required more than negligible resources include efforts performed with the Blackshear, Fessler, Harry, R. London, and Hu laboratories.